• Title/Summary/Keyword: field emitter

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Optimal Disposition of Direction Finder using EM Wave Propagation Analysis (전파환경분석을 통한 방향탐지기 최적배치에 관한 연구)

  • Yang, Jong-Won;Choi, Jun-Ho;Kwon, Do-Baeg;Kang, Hee-Seog;Park, Cheol-Sun
    • Journal of the Korea Institute of Military Science and Technology
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    • v.10 no.2
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    • pp.170-179
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    • 2007
  • This paper introduces the optimal disposition of direction finder using EM(Electro-magnetic) wave propagation analysis which is based on LR(Longley-Rice) propagation model and the characteristics of direction finder, emitter and terrain. Initial model is simulated and modified to minimize propagation error as a result of the field trials. Proposed analysis used line-of-sight analysis and mountain-top extraction algorithm to optimize the disposition in the assigned area and the result can be displayed in the 3D map in order of the percentage coverage for direction finding possibility area.

Conduction properties of phosphorescent emitting layers and their application to optimizing white OLEDs

  • Baek, Heume-Il;Noh, Seung-Uk;Lee, Hyun-Koo;Suman, C.K.;Lee, Chang-Hee
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.1055-1055
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    • 2009
  • The mobility of charge carriers has been investigated in the pristine and phosphorescent materials doped host materials using time-of-flight photoconductivity technique. The field and temperature dependences of the mobility were analyzed with the Gaussian disorder model. Based on these results, we optimized white organic light emitting diodes (WOLEDs) consisting of multi-emitting layers doped with phosphorescent and fluorescent dopants. Especially, we studied the effect of each emitter position and an interlayer on the device characteristics of WOLEDs.

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A Novel EST with Trench Electrode to Immunize Snab-back Effect and to Obtain High Blocking Voltage

  • Kang, Ey-Goo;Sung, Man-Young
    • Transactions on Electrical and Electronic Materials
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    • v.2 no.3
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    • pp.33-37
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    • 2001
  • A vertical trench electrode type EST has been proposed in this paper. The proposed device considerably improves snapback which leads to a lot of problems of device applications. In this paper, the vertical dual gate Emitter Switched Thyristor (EST) with trench electrode has been proposed for improving snab-back effect. It is observed that the forward blocking voltage of the proposed device is 745V. The conventional EST of the same size were no more than 633V. Because the proposed device was constructed of trench-type electrodes, the electric field moved toward trench-oxide layer, and the punch through breakdown of the proposed EST is occurred at latest.

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High vacuum packaging and vacuum evaluation for field emission display

  • Jung, S.J.;Woo, K.J.;Lee, N.Y.;Ahn, S.;Moon, G.J.;Kim, K.S.;Kim, M.S.
    • Journal of Korean Vacuum Science & Technology
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    • v.3 no.1
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    • pp.95-97
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    • 1999
  • A 3.12" FED panel was packaged successfully using the anode plate on which phosphors and black matrix were coated and cathode plate containing emitter arrays. The vacuum level of the panel was investigated during panel evacuation, tip-off and getter activation process. The packaged panel exhibited vacuum level below 2${\times}$10-6 Torr. Similar experiments were carried out for 10" panel made of bare plates. In addition, the vacuum level of two panels was compared continuously after tip off process; one with the getter and the other without it.

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Merging, Recoiling, or Slingshotting of Supermassive Black Holes in a Red AGN 1659+1834

  • Kim, Dohyeong;Im, Myungshin
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.1
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    • pp.31.1-31.1
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    • 2021
  • We report the Gemini Multi-Object Spectrograph (GMOS) Integral Field Unit (IFU) observation of a red active galactic nucleus (AGN), 2MASSJ165939.7+183436 (1659+1834). 1659+1834 is a prospective merging supermassive black hole (SMBH) candidate due to its merging features and double-peaked broad emission lines. The double-peaked broad emission lines are kinematically separated by 3000 km/s, with the SMBH of each component weighing at 10^8.9 and 10^7.1 solar mass. Our GMOS IFU observation reveals that the two components of the double-peaked broad emission line are spatially separated by 0.085" (~250pc). In different assumptions for the line fitting, however, a null (<0.05") or a larger spatial separation (~0.15") are also possible. For this GMOS IFU observational results of 1659+1834, various models can be viable solutions, such as the disk emitter and multiple SMBH models. We believe that these results show the need for future research of finding more multiple SMBH systems in red AGNs.

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Advances in Intrinsically Stretchable Light-Emitting Diodes (본연적 신축성을 갖는 발광 다이오드 개발 동향)

  • Wonjin Koh;Moon Kee Choi
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.36 no.6
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    • pp.537-546
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    • 2023
  • Intrinsically stretchable light-emitting diodes, composed of stretchable electrodes, charge transport layers, and luminescent materials, have garnered significant interest for enhancing human well-being and advancing the field of deformable electronics. Various luminescent materials, such as perovskites and organics, have been integrated with stretchable elastomers to function as the stretchable emissive layers in these intrinsically stretchable LEDs. Stretchable conductors including Ag nanowire based percolating structures and conducting polymers have been utilized as stretchable transparent electrode. Despite this progress, their performances in terms of efficiency and stability remain challenging compared to their structurally stretchable and rigid LED counterparts. This review offers a comprehensive overview of recent advancements in intrinsically stretchable LEDs, focusing on material innovations.

Characteristics of $SiN_x$ films on wet-etched Si for field emission device (전계 방출 소자용으로 제조한 단결정 실리콘 기판에 증착된 실리콘 질화막에 대한 특성 연구)

  • Jung, Jae-Hoon;Ju, Byeong-Kwon;Lee, Yun-Hi;Oh, Myung-Hwan;Jang, Jin
    • Proceedings of the KIEE Conference
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    • 1995.07c
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    • pp.1137-1139
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    • 1995
  • $SiN_x$ films deposited on bare Si and wet-etched Si by RPCVD were fabricated to investigated the effect of wet-etched surface of Si on the characteristics of the interface between $SiN_x$ and Si. FT-IR spectra on each film showed similar characteristics. However, it was confirmed that the electric characteristics(I-V, C-V) of the interface between $SiN_x$ and Si have been degraded by the wet etching process of Si, which is applied for the formation of Si field emitter array. Therefore, we suggest that the stacked structure of insulating layer with good interface characteristics is desirable for FED application.

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Fabrication of Triode-Type CNT-FED by A Screen-printing of CNT Paste

  • Kwon, Sang-Jik;Shon, Byeong-Kyoo;Chung, Hak-June;Lee, Sang-Heon;Choi, Hyung-Wook;Lee, Jong-Duk;Lee, Chun-Gyoo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.866-869
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    • 2004
  • A carbon nanotube field emission display(CNT FED) panel with a 2 inch diagonal size was fabricated by using a screen printing of a prepared photo-sensitive CNT paste and vacuum in-line sealing technology. After a surface treatment of the patterned CNT, only the carbon nanotube tips are uniformly exposed on the surface. The diameter of the exposed CNTs are usually about 20nm. The sealing temperature of the panel was around 390 $^{\circ}C$ and the vacuum level was obtained with $1.4{\times}10^{-5}$torr at the sealing. The field emission properties of the diode type CNT FED panel were characterized Now, we are developing a triode type CNT FED with a self-aligned gate-emitter structure.

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Characterization of Triode-type CNT-FED Fabricated using Photo-sensitive CNT Paste

  • Kwon, Sang-Jik;Chung, Hak-June;Lee, Sang-Heon;Choi, Hyung-Wook;Shin, Young-Hwa;Lee, Dal-Ho;Lee, Jong-Duk
    • Journal of Information Display
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    • v.5 no.4
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    • pp.18-22
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    • 2004
  • A carbon nanotube field emission display (CNT FED) panel with a 2 inch diagonal size was fabricated through screen printing of a prepared photo-sensitive CNT paste and vacuum in-line sealing technology. After surface treatment of the patterned CNT, only the carbon nanotube tips are uniformly exposed on the surface. The diameter of the exposed CNTs are usually about 20nm. The sealing temperature of the panel is around 390 $^{\circ}C$ and the vacuum level is obtained with $1.4{\times}10^{-5}$torr at the sealing. The field emission properties of the diode type CNT FED panel are characterized. Currently, we are in the process of developing a triode type CNT FED with a self-aligned gate-emitter structure.

Fabrication of Novel Metal Field Emitter Arrays(FEAs) Using Isotropic Silicon Etching and Oxidation

  • Oh, Chang-Woo;Lee, Chun-Gyoo;Park, Byung-Gook;Lee, Jong-Duk;Lee, Jong-Ho
    • Journal of Electrical Engineering and information Science
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    • v.2 no.6
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    • pp.212-216
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    • 1997
  • A new metal tip fabrication process for low voltage operation is reported in this paper. The key element of the fabrication process is that isotropic silicon etching and oxidation process used in silicon tip fabrication is utilized for gate hole size reduction and gate oxide layer. A metal FEA with 625 tips was fabricated in order to demonstrate the validity of the new process and submicron gate apertures were successfully obtained from originally 1.7$\mu\textrm{m}$ diameter mask. The emission current above noise level was observed at the gate bias of 50V. The required gate voltage to obtain the anode current of 0.1${\mu}\textrm{A}$/tip was 74V and the emission current was stable above 2${\mu}\textrm{A}$/tip without any disruption. The local field conversion factor and the emitting area were calculated as 7.981${\times}$10\ulcornercm\ulcorner and 3.2${\times}$10\ulcorner$\textrm{cm}^2$/tip, respectively.

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